Consciousness is related to sentience, or is an awareness of one's existence. However, it remains mysterious and controversial, despite being a familiar aspect of our lives. Sometimes, it is synonymous with the mind, and at other times, an aspect of mind. It is related to cognition, experience, feeling, perception, awareness, and self-awareness. A great debate is about whether only humans are conscious, all animals, or even the whole universe.
Consciousness is the last refuge of human exceptionalism - Anil Seth.
The human search for the structure of the universe is more important than finding it because it motivates the creative power of the human imagination - John Barrow.
Kaku's definition[]
Michio Kaku, frustrated with everyone "debating ghosts", came up with a definition of consciousness in his book The Future of the Mind.
"It is the sum total of all the feedback loops necessary to create a model, a model of yourself in space and time in society.
The simplest level of consciousness is a thermostat. A thermostat has one feedback loop, and it creates a model of itself in temperature. It regulates the temperature in a room. So I say that a thermostat has one unit of consciousness.
A plant has maybe 10 units of consciousness. It’s conscious of its temperature, moisture, direction of the sun, oxygen, carbon dioxide content, a few sensors that give you maybe 10 feedback loops.
The next level of consciousness is a reptile. A reptile has an understanding of space, but not much more. It has to understand where the food is located, where its potential mates are, where its enemies are. So it has to be able to create feedback loops that understand space, its location in space. So I call that level one. Level one consciousness is the thousands of neurons necessary to create a representation of space for a reptile. That’s called the reptilian brain.
Then at the center of the brain, because the brain evolves from the back to the front, the back of the brain is the reptilian brain. The center of the brain evolved later, and that’s the monkey brain, the limbic system, and that governs consciousness in society.
So what is human consciousness? What feedback loops does the human brain give a human that differs from monkeys, differs from reptiles? That is the key question of which I have an answer. The front part of your brain is what distinguishes us from the animals. And what does that brain do? It creates a model of yourself in time. It is a time machine. It daydreams. It imagines worlds that don’t exist.
A dog cannot understand the meaning of tomorrow. Your dog understands space. That’s the reptilian brain, the back of your brain. Your dog understands society, that is the society of dogs. That’s the center of the brain. But the front of the brain, the prefrontal cortex, is not well-developed in dogs. So dogs cannot daydream, and don't need to.
Humans on the other hand, constantly daydream. We can’t help it. We’re constantly imagining, what am I going to do tomorrow? What is the best path to go? It’s constantly creating alternate worlds of consciousness.
So I say that there are three levels of consciousness.
- There is location / geometric consciousness / spatial consciousness. That is the reptile.
- There is social consciousness of a monkey, or a wolf in a wolf pack.
- There is temporal consciousness, which is what humans do.
That is my definition of human consciousness. Human consciousness is the sum total of all feedback loops of a human assessing its place in time, essentially the future, and constantly daydreaming about what one can do in the future."
Daydreaming[]
Note that daydreaming is a stream of consciousness that detaches from current, external tasks when attention drifts and dissociates to a more personal and internal direction. This is different to dreaming, where images, ideas, emotions, and sensations occur involuntarily in the mind during certain stages of sleep. Animals can dream, but only humans can daydream.
Humans' daydreams are linked to their imagination, the ability to mentally envision a tool or concept and then summon it into reality. All modern things originally only existed as thought forms inside someone’s mind. They were all once inert pieces of quantum possibility floating in the abstract realm of human imagination until we evolved the means to pursue their creation. If we only made choices regarding the external world, we would still be operating as apes, reacting to our bodily needs like sleep, warmth, hunger, etc. By internalizing, we became curious apes and were able to manifest our thoughts to manipulate reality.
Daydreaming is in the realm of dreams, or surreality. This is outside of spacetime and dimensions. Does this mean that human consciousness is stored elsewhere, and there is a physical connection between your mind and an out-of-mind, out-of-body storage?
Collapse of the Wave function[]
The collapse of the wave function is a concept from quantum mechanics that explains how particles, which can exist in multiple states at once (superposition), seem to "choose" a definite state when observed or measured. Before measurement, a particle (like an electron) exists in multiple possible states simultaneously (superposition). It can be in several locations at once, described by a wave function, which is a mathematical description of all the possible states a particle can be in. It’s like a cloud of probabilities where each point represents a different possibility for the particle’s position, speed, etc. When we measure or observe the particle, the wave function "collapses," and the particle is found in only one specific state (like one definite location). The other possibilities "disappear," and the particle behaves like it has always been in that state.
Schrödinger’s cat is a thought experiment where the cat is in a box and is both alive and dead (superposition) until someone opens the box and looks. Observing the cat forces it to be either alive or dead (collapse).
The connection between consciousness and the collapse of the wave function stems from interpretations of quantum mechanics, particularly how quantum states, which exist in a superposition of multiple possibilities, seem to "collapse" into one definite state when measured. The question is whether consciousness itself plays a role in this collapse.
The Copenhagen Interpretation of quantum mechanics suggests that the act of observation or measurement causes the wave function collapse. Some interpretations propose that consciousness—the act of a conscious observer measuring or observing a system—might be responsible for this collapse.
The Von Neumann-Wigner Interpretation explored the idea that consciousness itself is required to collapse the wave function. This interpretation, sometimes called the "consciousness causes collapse" theory, suggests that the observer’s awareness has a direct impact on determining physical reality.
The Orch-OR theory (below) suggests a direct link between consciousness and quantum processes, including the collapse of the wave function.
Most physicists and neuroscientists reject the notion that consciousness causes the collapse of the wave function. They typically favor interpretations that do not invoke consciousness, such as the Many-Worlds Interpretation or Decoherence, which explain collapse as a result of interactions with the environment rather than the need for an observer.
Orchestrated Objective Reduction (Orch-OR) theory[]
The Orchestrated Objective Reduction (Orch-OR) theory, proposed by Roger Penrose and Stuart Hameroff, suggests that quantum processes within microtubules in neurons could be integral to the emergence of consciousness.
Microtubules are tiny, tube-like structures found inside cells, including neurons in the brain. They help maintain cell structure and support intracellular transport. According to the Orch-OR theory, they could also process information at a quantum level.
The theory posits that microtubules can undergo quantum superposition, where particles exist in multiple states simultaneously. The collapse of this quantum state (objective reduction) could create discrete moments of conscious awareness. This collapse, theorized by Penrose, would occur in a manner tied to the structure of spacetime itself.
Penrose and Hameroff argue that the brain might use quantum computing via microtubules to give rise to consciousness. This would mean that consciousness is not merely the result of classical neural interactions but also involves deeper, quantum processes happening within the brain's microtubules.
The Orch-OR theory is controversial and not widely accepted by the scientific community. Most neuroscientists believe that consciousness and decision-making arise from classical, biochemical processes in the brain, rather than quantum effects in microtubules.
Global Workspace Theory (GWT)[]
The GWT explains consciousness as the brain's way of integrating and sharing information across various specialized neural networks. It suggests that a "global workspace" acts as a central hub, broadcasting relevant information to the rest of the brain to create unified, conscious awareness. This enables complex tasks like decision-making, problem-solving, and flexible behavior.
Attention Schema Theory (AST)[]
The AST suggests that consciousness arises as the brain's internal model of attention, which helps monitor and control focus on specific stimuli. This "attention schema" simplifies complex processes and provides a subjective experience of awareness, enabling better self-regulation and decision-making. Essentially, consciousness is viewed as the brain's way of understanding and managing its own attention.
Qualia[]
Qualia are instances of subjective, conscious experience. Examples include the perceived sensation of pain of a headache, the taste of wine, and the redness of an evening sky.